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s. A.-M ILLER. COMPOSITION FOR MAKING SEWER INVBRT BLOCKS. No. 336,732. Patented Feb. 23, 1886.

(No Model.)

INVBNTOR ATTORNEYS.

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. are '5 oroughiy mixed with'as small a quantity UNITED STATES PATENT OFFICE.

SAMUEL A. MILLER, OF PHILADELPHIA, PENNSYL ANIA.

COMPOSITION FOR MAKING .SEWER lNVERT-BLOCKS.

SPECIFICATION forming part of Letters Patent No. 336,732, dated February 23, 1886.

Application filed July 21, 1885. Serial No. 172,564. (No specimens.)

To all whom it may concern.-

Be it known that I, SAMUEL A. MILLER, of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented a new and Improved Composition for Making Sewer Invert-Blocks, of which the following is a full, clear, and exact description.

The object of my invention is to provide certain new and useful improvements in the method of making and in the composition of sewer invert-blocks, whereby I obtain blocks that are solid and strong, cheap and durable, and can be made easily and rapidly.

Reference is to be had to the accompanying drawings, forming part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figure 1 is a cross-sectional elevation of my improved sewer invert-block mold and a block in the same. Fig. 2 is a perspective view of my improved sewer invert-block.

e blockq's formed of the following composition: hvdraulic cement p e p-a;

' two partsmmtgne pgrt; Iron 'or' steel "since one, pa rt.. eseingredlenls of water as possible. This composition is then filled Into the mold A, the bottom block, B, of which is shaped the same as the top of the sewer invert-block, and then the composition is rammed down. Before filling the mortar D into the mold I spread a thin layer, 0, of a mixture of one part of sand and one part of cement on the face of the bottom block, B, of the mold. This latter mixture appears on the top surface of the invert-block and gives the top a hard and smooth finish. The rest of the block is made to have great strength and durability, and to resist great pressure.

In place of the composition specified any other composition of matter may be used that would produce a hard and durable article of stone.

Having thus described my invention, what I claim as new, and desire to secure by Letters 5 Patent, is

A sewer in vert-block made of artificial stone.

SAMUEL A. MILLER. 

